EDEN PRAIRIE, Minn. -- The Minnesota Vikings appear to be at least exploring options to upgrade at safety, and one of their first calls went to one of the NFL's best.

The agent for free agent Eric Weddle said by e-mail early Tuesday afternoon he and the Vikings have been "in constant contact since this (morning) about a lot of different things," including the standout safety.

David Canter, who has more than 20 clients on NFL rosters, said Weddle had no visits scheduled roughly three hours after the free-agent negotiation period opened. Another Canter client, receiver Freddie Brown, was told by the Vikings he will be released.

Weddle, 26, was a second-round draft pick (37th overall) in 2007 out of Utah. The 5-11, 200-pound California native has started all but three games over the past three seasons with the San Diego Chargers.

In 60 career games (not including playoffs), Weddle has 358 tackles (295 solo), four sacks, six inteceptions and 28 passes defended. Five other teams, including the Chargers, reportedly have shown interest.

The first training camps are set to open around the league on Thursday and a 5 p.m. Friday starting line looms for free agents to begin signing contracts, although they won't be allowed to practice until the new league year begins on Aug. 4.

The biggest question may not be whether the Vikings are interested, but whether they can compete financially with a top-heavy payroll and a long list of in-house free agents headed by receiver Sidney Rice.

When the negotiation period opened at 10 a.m. Tuesday, the Vikings were about $4.8 million over the salary cap, according to an NFL source. They will trim $2.5 million from the cap when the anticipated release of defensive tackle Jimmy Kennedy becomes official on Thursday afternoon and are expected to make several other moves before then.

Signing Weddle or another veteran safety probably would spell the end in Minnesota for Madieu Williams, who hasn't been approached by the Vikings about possibly restructuring and would object if asked to rework a deal that's set to pay him $5.4 million in base salary and $100,000 workout bonus this year, an NFL source said.

Williams, 29, has three years and $16.5 million remaining on a six-year deal that already was negotiated once for cap purposes in December 2009. Cutting him would save the Vikings nearly $3.5 million against this year's cap.

Vikings coach Leslie Frazier has expressed a desire to retain Williams, particularly with the lockout eliminating a chance to continue grooming younger backups Tyrell Johnson and Jamarca Sanford. But his sizeable cap number and salary make it worth questioning what chance Williams has of sticking around, given his waning production and injury history.

The Vikings' other starting safety, Husain Abdullah, is a restricted free agent and could wait as late as Aug. 20 to see if he would receive an offer sheet. But Abdullah's agent, CJ LaBoy, said his client is "100% going to sign (the tender) on Friday. Husain can't wait to get back to work."